By Nicholas Stehle
November 17, 2015
You’ve probably seen it on television or in film, or read it in a fictional story: characters find a wormhole and use it to travel backwards or forwards through space or even time. Some scientists believe there might be an element of truth to that.
According to physicist Eric Davis, “A traversable wormhole is a hyperspace tunnel, also called a throat, that connects together two remotely distant regions within our universe, or two different universes — if other universes exist — or two different periods in time, as in time travel, or different dimensions of space.”
Davis is trying to use Einstein’s general theory of relativity to design traversable wormholes, warp drives, and even time machines. This might be difficult: no one has ever seen a wormhole, and based on current theories it is unlikely that an open wormhole would stay open long enough for a person to traverse it.
But according to one scientist, dark matter may hold the key to one day finding experimental evidence. Ali Övgün of Eastern Mediterranean University in Cyprus says it is possible that wormholes could form with the presence of dark matter inside galactic halos, which his simulations show would provide the physical requirements that he and his colleagues believe would be required to form a traversable tunnel.
For now, we’ll have to put hope in his simulations: all he can provide for now is mathematical proof.
And hope we will: Davis believes that no harm would come to the person or spaceship attempting to traverse the black hole: “The space-time geometry of traversable wormholes requires that there be no nasty, intolerable gravitational tidal forces acting upon the spacecraft or its passengers while they move through the wormhole tunnel,” he said. “They go into the throat at their departure location near Earth and get shunted through the tunnel to emerge out the other side near the destination star.”
If the tunnels do cut through space-time as has been suggested, the tunnels could help humans achieve FTL (faster than light) travel. But we’d have to find them, first: and since we’ve already established that one has never been found, that could be a chore.
Time travel may prove even more difficult still. “It would be extremely difficult to construct a wormhole time machine,” Davis said. “It’s relatively much simpler to use wormholes for FTL interstellar travel between the stars.”
Still, time travel could have its benefits. “Think of all the possibilities of what people could do and the discoveries they could make if they could travel through time,” Davis said. “Their adventures would be very interesting, to say the least.”
As NASA selects astronauts for a mission that will one day lead humanity to Mars, it’s as good a time as any to contemplate these things.